ELECTIVE occlusion of major vessels proximal to vital structures in normothermic animals and humans has been limited in time because of tissue necrosis following prolonged ischemia. The known effect of general hypothermia in reducing tissue metabolism suggested the possibility of utilizing this technique as a means for prolonging regional ischemia without tissue or organ damage. The desirability of an essentially bloodless field for certain surgical procedures is obvious and has interested many clinical investigators in the past.
Raffuci and Wangensteen,12 in 1950, found that the maximal safe period of occlusion of the hepatic artery and portal vein in normal dogs was 20 minutes. Lengthening the occlusion time produced hepatic necrosis. Burch and his colleagues,5 in 1953, successfully resected a temporarily bloodless left lobe of the liver in two patients while occluding the aorta above the celiac axis for 10-minute intervals. Both of these reports were during normothermia. Increasing